title: Strengthening effect of single-atomic-layer graphene in metal-graphene nanolayered composites.
abstract: Graphene is a single-atomic-layer material with excellent mechanical properties and has the potential to enhance the strength of composites. Its two-dimensional geometry, high intrinsic strength and modulus can effectively constrain dislocation motion, resulting in the significant strengthening of metals. Here we demonstrate a new material design in the form of a nanolayered composite consisting of alternating layers of metal (copper or nickel) and monolayer graphene that has ultra-high strengths of 1.5 and 4.0 GPa for copper-graphene with 70-nm repeat layer spacing and nickel-graphene with 100-nm repeat layer spacing, respectively. The ultra-high strengths of these metal-graphene nanolayered structures indicate the effectiveness of graphene in blocking dislocation propagation across the metal-graphene interface. Ex situ and in situ transmission electron microscopy compression tests and molecular dynamics simulations confirm a build-up of dislocations at the graphene interface.
authors.affiliation: Graduate School of Energy Environment Water and Sustainability, Korea Advanced Institute of Science & Technology, Daejeon 305-701, Korea.
authors.forename: Youbin
authors.initials: Y
authors.lastname: Kim
authors.forename: Jinsup
authors.initials: J
authors.lastname: Lee
authors.forename: Min Sun
authors.initials: MS
authors.lastname: Yeom
authors.forename: Jae Won
authors.initials: JW
authors.lastname: Shin
authors.forename: Hyungjun
authors.initials: H
authors.lastname: Kim
authors.forename: Yi
authors.initials: Y
authors.lastname: Cui
authors.forename: Jeffrey W
authors.initials: JW
authors.lastname: Kysar
authors.forename: James
authors.initials: J
authors.lastname: Hone
authors.forename: Yousung
authors.initials: Y
authors.lastname: Jung
authors.forename: Seokwoo
authors.initials: S
authors.lastname: Jeon
authors.forename: Seung Min
authors.initials: SM
authors.lastname: Han